目的 研究FeCoCr0.5NiBSix高熵合金在高温冲蚀下的表面形貌、冲蚀机理和磨损性能。方法 在45钢基体上用激光熔覆方法制备FeCoCr0.5NiBSix（x=0.1~0.4）高熵合金涂层，将不同Si含量的FeCoCr0.5NiBSix高熵合金涂层分别在室温和650~900 ℃下进行冲蚀试验。利用SEM和EDS等方法分析涂层截面和表面冲蚀形貌，同时测试涂层的显微硬度和冲蚀磨损率。结果 FeCoCr0.5NiBSix涂层由简单FCC固溶体和硼化物两相组成，Si元素易固溶在FCC固溶体中。FeCoCr0.5NiBSix涂层的冲蚀形貌在低角度冲蚀下以犁沟和切削为主，而在高角度下则出现挤压坑。随着Si添加量的增加，FeCoCr0.5NiBSix涂层的硬度先下降后升高，这与涂层在低角度下的冲蚀磨损率规律相反，而与高角度下的规律一致。FeCoCr0.5NiBSix涂层的冲蚀磨损规律正好与304不锈钢相反，其冲蚀磨损率均随着冲蚀攻角和温度的增加而明显增大，30°攻角下呈现出最小的冲蚀磨损率（8.2 mg/cm2）。结论 FeCoCr0.5NiBSix涂层的冲蚀磨损机理类似于脆性材料，低角度下以切削和犁沟破环形式为主，高角度下则以挤压破环和脆性破碎形式为主。FeCoCr0.5NiBSix涂层在低角度下的冲蚀磨损性能明显好于304不锈钢。

The work aims to study the eroded morphology, erosion mechanism and erosive wear properties of the FeCoCr0.5NiBSix high-entropy alloy at high temperature. The FeCoCr0.5NiBSix (x=0.1~0.4) high-entropy alloy coating was pre-pared on 45 steel substrate by laser cladding. The high-temperature erosion tests were performed to the FeCoCr0.5NiBSix coating with different Si content at room temperature and 650~900 ℃ respectively. The cross section and eroded surface morphology of the FeCoCr0.5NiBSix coating were analyzed by SEM and EDS. The microhardness and erosion rate of the coatings were also measured. The FeCoCr0.5NiBSix coating was composed of simple FCC solid solution and boride, and the Si element was easy to be dissolved in the FCC solid solution. The erosion morphology of the FeCoCr0.5NiBSix coating was dominated by ploughing and cutting at low impact angles, while the indenting morphology appeared at high impact angle. With the increase of Si, the hardness of FeCoCr0.5NiBSix coating decreased first and then increased, which was opposite to the erosion rate of the coating at low impact angle, and was consistent with the law at high impact angle. The erosive wear law of the FeCoCr0.5NiBSix coating was exactly opposite to that of 304 stainless steel, and the erosion rate of the FeCoCr0.5NiBSix coating increased with the increase of impact angle and erosion temperature. The minimum erosion wear rate of the FeCoCr0.5NiBSix coating was 8.2 mg/cm2 at impact angle of 30°. The erosive wear mechanism of the FeCoCr0.5NiBSix coating is similar to that of brittle materials, namely the cutting and ploughing damage at low impact angle, and the extrusion damage and brittle fracture at high impact angle. The erosion rate of the FeCoCr0.5NiBSix coating is obviously better than that of 304 stainless steel at low impact angle.